Process for dehydrogenating hydrogenated polycyclic phenols



Patented July 27, 1937 d v I UNITED STATES PATENT OFFICE PROCESS FORDEHYDROGENATING HY- DROGENATED POLYCYCLIC PHENOLS Wilbur A. Lazier, NewCastle County, Del., assignor to E. I. du Pont de Nemours & Company,Wilmington, Del., a corporation of Delaware No Drawing. ApplicationMarch 1936 Serial No. 67,305

26 Claims. (01. 260-131) This invention relates to catalytic processesaltogether. A full description of this invention and more particularlyit relates to processes for is contained in the following selectedexamples. the removal of hydrogen from organic hydroxy le compounds oversuitable dehydrogenat'mg base ramp metal ysts. More specifically thisinvention Fifteen hundred grams of copper nitrate, dis- 5 relates toprocesses for the liquid phase dehydrosolved in 4 liters of water, wasmixed witha solugenation of hydrogenated polycyclic phenols over tioncontaining 1000 grams of ammonium c r0- copper chromite catalysts. matein an equal volume of water. Ammonium This application is acontinuation-in-part of hydroxide was added to neutralize the acidity mypending application, Serial No. 713,922, filed developed duringprecipitation of the copper am- 10 March 3, 1934 monium chromate. Theprecipitate was filtered, Catalytic dehydrogenation processes have beendried, and ignited at a. temperature of 400 C., used for many years forthe preparation of aldeafter which it was extracted twice with dilutehydes and ketones from the corresponding priacetic acid. The resultingcopper chromite powmary and secondary alcohols. Most of the disder wasemployed for dehydrogenation without 15 closures in the literature havebeen concerned further treatment. with vapor phase processes operated athigh tem One hundred fifty grams of hydrogenated diperatures andemploying catalysts which were 'phenylolpropane (di-4-hydroxycyclohexyldicomparatively inactive. A number of the prodmethyl methane) and 15grams of copper chroucts which have been prepared by the catalytic mitecatalyst prepared. as .described above, .are processes of this inventionhave long been known placed in a flask equipped with a stirring device.in the older literature. Cyclohexyl cyclohexa- The mixture'is heatedthrough a temperature none-2 cyclohexyl cyclohexanone-'4,ac-beta-tetrange of 180 C. to 266 C. over a period of 15 ralone andbeta-decalone have all been prepared hours. At the end of that time 99percent of by chemical oxidation of the corresponding hythe theoreticalquantity of hydrogen is evolved.

droxy compounds. On the other hand, the resins The product isdissolvedin acetone, filtered to refrom the dehydrogenation of hydrogenateddimove the catalyst, and the solvent evaporated phenylolpropane,hydrogenated diphenylocyclounder diminished pressure. The product is ahexane, hydrogenatedphenol-formaldehyde reshard, brittle, amber coloredresin which softens ;0 ins and naphthenyl cyclohexanol, and themonobetween 60 and 70 C. Itis soluble in acetone, meric ketones 4-phenylcyclohexanone and bis-2, alcohol, and other organic solvents. The yield2-(3-methyl-4-ketocyclohexyl) dimethyl methane is nearly quantitative.Analysis indicates the are new compositions of matter. presence ofapproximately one ketoni'c oxygen This invention has as an object theconversion for each diphenylolpropane nucleus. The reof hydroaromaticsecondary hydroxy compounds maining oxygen is eliminated. and collectedas to ketonic compounds by removal of hydrogen. water during the courseof the dehydrogenation A further object is the liquid phase catalyticdereaction. The resin is apparently formed by ranhydrogenation ofhydrogenated polycyclic phedom condensation of the diketonecorresponding nols to polycyclic ketones or ketone resins over t ddecahydrodiphenylolplopalie simil r to t L0 copper chromite and othereflicient catalysts. condensation of cyclohexanone, etc., to resins. 40A still further object is to prepare new and use-' T extent, fpolymerization is markedly ful coltmosifions of matter by the liquidPhase creased by traces of alkalies in the dehydrogenacata'lytlcdehydmgenatlon of ydmgenated poly tion mixture or by heating theisolated resin with cyclic phenols. r h r almost :5 These objects areaccomplished by means of alkalies. The material becomes toug e thefollowing invention which is the result of an mfusiple and ,veryinsoluble; extended investigation on the liquid phase dehy- Example 2drogenation of hydrogenated polycyclic phenolic bodies. This inventioncomprises bringing the Flfty gram of dodecahydmdlphenylolcyclohex 0 hdro enated' lycyclic henol into contact with ane a dehgdrogena ng catalyst, heating at temperais dehydmgenated m maPner F to that tures in therange from 50 c, t 400 Q at pres described in Example 1. Elghty-mne andtwosures sufiicient to overcome the vapor pressure tenths P cent of thetheoretical amount of of the material under treatment until hydrogendrogen s evo ved in hou a temperatures 5 is evolved in the theoreticalquantity or ceases --rangingfrom 223 C. to 285 C. The product islikewise an amber colored resin similar to the resin fromdodecahydrodiphenylolpropane.

Example 3 Two hundred eighty grams of dodecahydrodi-ocresylolpropane(bis-2, 2-(3-methyl-4-hydroxycyclohexyl) propane) is dehydrogenated withcopper chromite catalyst at atmospheric pressure and temperaturesranging from 185 C to 261 C. Ninety-five and three-tenths per cent ofthe theoretical amount of hydrogen is evolved in 11 hours. Contrary toexpectations the major portion of the product is not a resin but themonomeric diketone, bis-2, 2-(3-methyl-4-ketocyclohexyl) propane,boiling point 185-189 C./2 mm. A

small amount of low-boiling material is encountered in the foreshot andthe distillation residue is a hard, brittle resin. The yield of diketoneis 60 percent. This unexpected result is probably due to the presence ofthe methyl groups attached to carbon atoms adjoining the ketone groupsformed in the reaction. These prevent condensation at that point andlikewise retard the rate of dehydrogenation and polymerization.

Example 4 Two hundred twenty grams of a hydrogenated phenol-formaldehyderesin containing free secondary hydroxyl groups is charged into a flaskwith 22 grams of copper chromite catalyst. The mixture is heated slowlyand is not stirred until the resin becomes molten. The evolution ofhydrogen begins at 190 and continues over a period of 10 hours. At theend of that time the temperature is at a maximum of 265 C. and the flowof gas ceases. Thetotal amount of hydrogen given 011 is 24.6 liters. Theproduct is isolated in the usual manner and, is a hard, brittle, ambercolored'resin. It is only partially soluble in acetone and alcohol butdissolves readily in toluene to form a viscous solution.

The amount of hydrogen given off indicates the presence of approximatelyone ketonic group to' three cyclohexane groups in the originalhydrogenated resin.

Example 5 One thousand grams of cyclohexyl cyclohexanol-4 and grams ofcopper chromite catalyst are charged into a flask equipped with amechanical stirring device. The mixture is heated at atmosphericpressure through a-temperature range of 198 C. to 255 C. and at the endof 5.3 hours the amount of hydrogen evolved indicates 60 per centconversion to the, ketone.

The product is taken upJin acetone, filtered to grams of cyclohexylcyclohexanone-4, boiling point 112 to 114 C./3 mm. The amount ofunchanged alcohol is about 400 grams.'

' Example 6 Fifty grams of cyclohexyl' cyclohexanol-2 is dehydrogenatedin a manner similar to that described in Example 1. The catalyst used iscopper chromite, the temperature of the reaction varies between 237 C.and 263 C., and the extent of hydrogen evolution is 75 per cent. The

Fifty grams of 4-phenyl cyclohexanol and 5 grams of copper chromitecatalyst are charged into a small flask equipped with a stirring device.The mixture isheated over a period of 9 hours at atmospheric pressureand through a temperature range from C. to 230 C. At the end of thattime 59 per cent of the theoretical amount of hydrogen is evolved. Theproduct is dissolved in alcohol and shaken with an'excess of saturatedsodium bisulflte solution. A sodium bisulflte addition compoundseparates as a white crystalline precipitate which is filtered, washedwith alcohol and dried. Decomposition of the sodium bisulflte derivativeis eflected by warming with dilute sodium carbonate solution and 22.5,-grams of crude solid ketone separates. Recrystallization from ligroingives 20 grams of 4- phenyl cyclohexanone, melting point 76 to 77 C., anew composition of matter.

Example 8 ,unchanged naphthenyl cyclohexanol, is a soft, sticky resinformed by thermal polymerization of the ketone.

' Example 9 One hundred eight grams of beta-decalol(decahydro-beta-naphthol) and 10.8 grams of copper chromite catalyst arecharged into a flask and heated, with stirring, .over a temperature of180 C. to 247 C. in 1.3 hours. The theoretical quantity of hydrogennecessary for the conversion of the alcohol to the ketone is evolved inthat time. The product is dissolved in acetone, filtered, and thesolvent evaporated. The crude residue is heated from 1 to 5 hours atl35to 140 C. with 50 grams of phthalic anhydride and the mixturefractionated. The distillate dilute alkali to extract the phthalicanhydride and redistilled. Forty-eight grams of 'pure betadecalone,boiling point 120 to 122 C./18 mm. is

obtained.

Example 10 Thirty-three grams of beta-decalol together with 3.3 grams ofcopper carbonate catalyst is charged into a flask equipped with athermometer, mechanical stirrer and condenser. A gas exit tube leadsfrom the latter through an ice trap to a wet test flow meter. The'mixture is is washed with' heated to C. whereupon the evolution ofhydrogen -gas begins. The hydrogen gas ceases to flow at a maximumtemperature of 225 C. after an apparent conversion of 97.5 per centbased on the amount of hydrogen evolved. The

product is isolated by the same procedure employed in Example 9. A goodyield of beta- 7 dered dehydrogenating metals may be prepared,

catalysts disclosed are particularly suitable for Although in the aboveexamples certain defi nite conditions of temperature, pressure, amountsof materials, durations of reactions, etc/have.

been indicated, it is to be understood that these values may be variedsomewhat within the scope of the invention since the particularconditions of operation are governed by the materials selected fortreatment and the type of catalyst employed. The processes described inthis invention are operative within the temperature range from 50 C. to400 C. and in a pressure range from below atmospheric pressure to amaximum necessaryto overcome the vaporpressure of a given material undertreatment. We prefer to operate at a temperature within the range from170 C. to 260 C. In general, it will seldom be necessary to-usepressures higher than atmospheric because of the relatively high boilingpoints of all substances that come within the scope of this invention.Pressures above 35 atmospheres tend to reverse the reaction. In itsbroadest aspects, this invention contemplates the employment of liquidphase dehydrogenation cat-' alysts'which, effect the liberation ofhydrogen from secondary carbinol groups in preference to dehydration.These catalysts employed in the practice of this invention are compoundsof the elements of Group 1, subgroup B, and Group II, subgroup B, in thePeriodic table. Copper containing catalysts such as powdered copper,powdered copper bronze, copper oxide, copper carbonate, or copperchromite are preferred in the practice of this invention. Catalystcompositions such as those containing silver, cadmium, zinc, etc., andcombinations thereof or their oxides are suitable, but are somewhat lessdesirable.

' The catalysts of this invention are most effective ina finely dividedstate and numerous methods are available for their preparation. .Pow-

by electrodeposition, precipitation from solution by replacement and byreducing agents or by reduction of suitable compounds such as theoxides, hydroxides, or carbonates with hydrogen. Oxides are formed bydirect combination of the metals with oxygen or by thermal decompositionof hydroxides, carbonates and the like. Normal and basic carbonates ofdehydrogenating metals are precipitated from salt solutions by alkalimetal or other soluble carbonates- The preparation of a typical chromitecatalyst is outlined in Example 1, and a more extended description ofthese catalysts is given in U. S. Patent 1,746,- 782, issued on February11, 1930, U. S. Patent 1,964,000 issued June 26, 1934, and incopendingapplication'Ser. No. 713,922, filed March 3, 1934. Catalysts supportedon materials, such as kieselguhr, which exert a dehydrating effect aremarkedly inferior to unsupported catalysts.

It is apparent that the processes of this invention offer manyadvantages over the prior art. Most of the compounds which have beenstudied cannot be subjected to a vapor phase process because of theirlow volatilities and tendency to dehydrate and otherwise decompose atthe high temperatures required in vapor phase reactions. Myinvestigation has resulted in the discovery of a novel and highlyefiicient process whichis applicable to the dehydrogenation of sensitiveand non-volatile compounds as well as those more stable and volatile.The very active and eflicient the dehydrogenation of compoundsin theliquid -by incorporation of other phase at comparatively lowtemperatures. The

low temperature allows a long period of contact between the catalyst andcompound and keeps degradation and side reactions at a Furthermore, alarge variety of old and new products may be prepared which wouldotherwise be obtainable only through laboriousv and costly processes.

The processes of this invention result in the preparation of manyvaluable products. The ketone resins from hydrogenateddiphenylolpropane, hydrogenated diphenylcyclohexane, hydrogenatedphenol-formaldehyde rains, and the diketone from hydrogenateddicresylolpropane and are of potential value as ingredients in thefabrication of varnishes, coated fabrics, Cellophane, cellulose etherand ester films and plastics, etc. Furthermore, they may be used assofteners and modifying agents for rubber and rubber derivatives,phenol-formaldehyde resins, Glyptal and other resins. The resins fromthe monoketones may be employed in asimilar way. Cyclohexylcyclohexanone-2, cyclohexyl cyclohexanone-4, beta-decalone and 4-phenylcyclohexanone are of interest as wax blending agents, modifying agentsfor rubber and rubber derivatives and as components of creams, polishesand wax emulsions. They are also of potential-use as in the preparationof resin intermediates and for the formation and modification of resins.The more volatile products have distinctive odors which make them ofinterest'as. perfumes or perfume chemicals.

The above ketones are particularlyuseful as plasticizers and softenersfor cellulose ethers and esters. Cellulose ester compositions containingbeta-decalone have been made up as described in the following selectedexamples:

Example 11 Eighty parts by weight of cellulose acetate and 20 parts byweight of beta-decalone are given a preliminary treatment in a Wernerand Pileiderer mixer. The mixture is then transferred to a Banbury mixerand is milled thoroughly at 100 C. until a. uniform colloid is produced.This is cooled and pulverized to form a molding powder.

Example 12 Example 13 Fifteen parts by weight of cellulose acetate and3.7 parts of beta-decalone are mixed. with 75 parts of acetone. Themixture is agitated until complete solution is effected. Excellent filmsare prepared by spreading the solution on a flat surface and allowingthe solvent to evapo-' rate. The properties of the films are modifiedplasticizers, such as triphenyl phosphate, camphor, dibutyl phthalate,etc., with the mixture.

Since many apparently and widely different embodiments of this thereofexcept as defined in the following appended claims.

I claim:

1. The process for catalytically dehydrogenating hydrogenated polycyclicphenols, which comprises bringing into contact in the liquid phase ahydrogenated polycyclic phenol and a dehydrogenating catalyst at atemperature within the range of 50 C. to 400 C.

2. The process in accordance with claim 1 characterized inthat thereaction is carried out at temperatures within the range of C.-

to 260 C.

3. The process for catalytically dehydrogenating hydrogenated polycyclicphenols which comprises bringing into contact in the liquid phase ahydrogenated polycyclic phenol and a dehydrogenating catalyst at atemperature within the range of 50 C. to 400 C. and a. pressurenot'exceeding 35 atmospheres. 1

4. The process for catalytically dehydrogenating hydrogenated polycyclicphenols which comprises bringing into contact in the liquid phase ahydrogenated polycyclic phenol having at least one ring selected fromthe group consisting of aromatic and alicyclic rings, said ring beingjoined to the hydrogenated phenolic residue by a linkage selected fromthe group consisting of a carbon-carbon bond, a carbon bridge, and alinkage formed by condensation of the two rings in such a manner thattwocarbon atoms are shared between them, with a dehydrogenating catalystat a temperature within the range of 50 C. to 400 C.

5. The process in accordance with claim 4 characterized in that thereaction is carried out at a temperature within the range of 170 C. to260 C. and at a pressure not exceeding 35 atmospheres.

6. The process in accordance with claim 4 characterized in that thedehydrogenating catalyst is derived from a metal selected from the groupof elements comprising sub-group B of Group 1 and sub-group B of Group 2in the Periodic table.

7. The process n accordance with claim 4 characterized in that thecatalyst is a dehydrogenating chromite catalyst.

8. The process in accordance with claim 4 characterized in that thecatalyst is a dehydrogeriiaating predominantly copper containing catalys9. The process in accordance with claim 4 characterized in that thedehydrogenating catalyst comprises essentially copper chromite.

10. The process of catalytically dehydrogenating hydrogenated polycyclicphenols which comprises bringing into contact in the liquid phase thehydrogenated condensation product of a simple phenol and acompound-selected fromthe group consisting of aldehydes and ketones witha dehydrogenating catalyst at a temperature within the range of 50 C. to400 C. .11. The process in accordance with claim 10 characterized inthat the reaction is carried out at a temperature within the range of170 C. to

260 C. and at a pressure not exceeding 35 atmospheres.

characterized in that the dehydrogenating catalyst comprises essentiallycopper chromite.

' 16. The process in accordance with claim 10 characterized in that thehydrogenated polycyclic phenol is a soluble hydrogenatedphenolformaldehyde resin.

17. The process for catalytically dehydrogenating hydrogenatedpolycyclic phenols which comprises bringing into contact in the liquidphase a hydrogenated naphthol with a dehydrogenating catalyst at atemperature within the range of 50 C. to 400 C.

. 18. The process in accordance with claim 17 characterized in that thereaction is carried out at a temperature within the range of 170 C. to260 C. and at a pressure not exceeding 35 atmospheres.

19. The process in accordance with claim 17 characterized in that thedehydrogenating catalyst is derived from a metal selected from the groupof elements comprising sub-group B of Group 1 and sub-group B of Group 2in the Periodic table.

20. The process in accordance with claim 17 characterized in that thecatalyst is a dehydrogenating chromite catalyst.

21. The process in accordance with claim 17 characterized in that thecatalyst -is a dehydrogenating predominantly copper containing catalyst.

22. The process in accordance with claim 17 characterized in that thedehydrogenating catalyst comprises essentially-copper chromite.

23. The process in accordance with claim 17 characterized in that thehydrogenated polycyclic phenol is beta-decalol.

24. The process for catalytically dehydrogenating hydrogenatedpolycyclic phenols which comprises bringing into contact in the liquidphase hydrogenated phenols of the type R-XC6H10OH, where R is selectedfrom the group consisting of aromatic and alicyclic rings, and X isselected from the group consisting of a carbon bridge and acarbon-carbon bond with a dehydrogenating catalyst at a temperaturewithin the range of 50 C. to 400 C.

25. The process in accordance with claim- 24 characterized in that thehydrogenated polycyclic phenol is 4 phenyl cyclohexanol.

26. As a new composition of matter the product obtained by the liquidphase catalytic dehydrogenation of hydrogenated phenol-ketone andphenol-aldehyde condensation products.

WILBUR A. LAZIER.

